packages installed using pip can be uninstalled completely using
pip uninstall <package>
refrence link
pip uninstall is likely to fail if the package is installed using python setup.py install as they do not leave behind metadata to determine what files were installed.
packages still show up in pip list if their paths(.pth file) still exist in your site-packages or dist-packages folder. You’ll need to remove them as well in case you’re removing using rm -rf